European Patent Publication 410 137 to Bosch discloses the triggering of "specific information" when the current location of a vehicle corresponds to a triggering point within a street map, ie. "point triggering".
A system using Global Positioning Satellites (GPS) is disclosed in European Patent Publication 511 447 to Pioneer. In this system the position of an automobile is calculated by GPS and, when the automobile enters a pre-determined area, an audio-visual event relating to the area is triggered (see FIG. 1), ie. "area triggering".
Another prior art system is known from European Patent Publication 672 890 to Aisin. Aisin discloses a method of capturing Points of Interest (POIs) using a metaphorical "torch beam". The torch may be selectively switched between "high" and "low" beam and all POIs which fall within the beam are captured and played (see FIG. 2) in order of priority, ie. "beam triggering".
These known methodologies are too rudimentary to be functional in an environment where there may be multiple POIs in close proximity, where the apparatus roves in a non-fixed route manner, or where GPS data wanders, for example.